Thursday, December 15, 2011

Lab 5.1: Alka Seltzer Poppers

In our experiment, we recorded how long it took for a tablet of Alka Seltzer to build up enough pressure to pop the top off of a small canister. We changed around things like temperature, how crushed the tablet was, and the ratio of vinegar and water in the film canister. Our procedure was effective at determining how different variables affected the rate because we made the variables very far apart (For example, instead of putting 24 degrees Celsius and then doing 25 degrees Celsius, we did 0 and then 50.) It was important to keep a control, and only change one thing at a time. If we changed two variables at a time, we wouldn't know which contributed more to the cap popping faster or slower.

A higher temperature made the particles move faster, which gave them a higher chance to collide at higher speeds. The more the tablet was crushed, the faster the reaction rate, because there is more surface area for the vinegar to touch the Alka Seltzer. The more vinegar put in, the faster the reaction rate, because vinegar is a better reactant than water, and the water molecules just get in the way of the vinegar molecules touching the tablets. Our concentration of vinegar in our experiment was not consistent. We thought more vinegar would cause a faster reaction rate. Our data was misleading because we didn't push the top on hard enough, so it didn't create a good seal. Without the seal, air can escape, and not as much pressure will build up.

Enrichment: Sulfuric acid is a catalyst used in real life, It's a highly corrosive mineral acid. It is used in batteries for cares, and for oil refining.
Almost all enzymes are proteins. They speed up chemical reactions by converting substrates into different molecules, called products.